Spring-fork for bicycles



UNITED STATES PATENT OFFICE.

MERRELLON F. HARDNET'I, OF ATLANTA, GEORGIA.

SPRING-FORK FOR BIGYGLES.

Specification of Letters Patent. Patented June 15, 1920.

Application filed July 14, 1919. Serial No. 310,580.

useful Improvements in Spring-Forks for Bicycles, of which the following is a specification.

This invention relates to improvements in spring forks for bicycles, especially the front forks, the object ofthe invention being to provide an improved spring fork which serves to absorb shocks and thereby greatly promotes the comfort of the rider of a bicycle or motorcycle. in

With the above and other objects in view, the inventionconsists in the construction, combination and arrangement of devices hereinafter described and claimed.

In the accompanying drawings:

Figure 1 is a side elevation of a bicycle spring fork constructed and arranged in accordance with my invention.

Fig. 2 is a front elevation of the same.

Fig. 3 is a vertical sectional view of the same on the plane indicated by the line 33 of Fig. 1. p

Fig. 4 is a transverse sectional view of the same on the plane indicated by the line 4 1 of Fig. 1. f

Fig. 5 is a transverse section taken in-the plane indicated by the line 5-5 of Fig. 1.

Similar numerals of reference designate corresponding parts in all of the views of the drawings. I r

The spindle 1 of the front fork is provided at the lower end with a fork head 2. Said fork head has recesses 3 in opposite sides. The fork arms 41 have their upper ends provided with extensions 5 which are fitted in said recesses, the fork arms beingv secured detachably to the fork head by means of a bolt 6 which passes through the fork head and through the said extensions.

The axle 7 of the front wheel is mounted in blocks 8. The said blocks operate in vertical slots 9 with which the fork arms are provided and each block has a downwardly extending inner arm 10 and also has an upwardly extending outer arm 11. The inner arms engage and slide in recesses 12 in the inner sides and at the lower ends of the fork arms, and the arms 11 have thickenedlower portions 13 on their inner sides which engage and slide in recesses 14 in the outer sides and at the lower ends of the fork arms. Blocks 16 are secured by screws 17 in the upper ends of the slots of the fork arms and are provided with downwardly opening guide slots 18 in which the arms 11 of the blocks 8 operate. Coiled extensile springs 19 have their upper ends fitted in bores in the lower sides of the blocks 16 and their lower ends fitted in recesses in the upper ends ofthe blocks 8, said springs exerting their tension to support the load on the front fork and serving to absorb shocks and permitting the fork to move vertically relatively to the axle of the front wheel. The

inner and outer arms of the blocks 8 coact with the for-karms to equalize the movement of said blocks and to always hold the axle of the front wheel exactly at right angles thereto and the guide slots in the upper blocks 16 coact with the outer arms of the blocks 8 to also guide and control the move- A said blocks having inner and outer guide arms respectively engaging the inner and outer sides of the fork arms, means at the upper portions of the slots having guide slots in which the outer arms of the first-named blocks operate, and springs arranged between the blocks and said means and serving to absorb shocks.

2. A bicycle fork, having arms each pro vided with a vertical slot, blocks forming bearings for a wheel axle and arranged for movement in the lower portions of the slots, said blocks having inner and outer guide arms respectively engaging the inner and outer sides of the fork arms, blocks secured in the upper portions of the slots and having guide slots inwhich the outer arms of the first named blocks operate, and springs arranged between the first named blocks and the last named blocks and serving to absorb shocks.

In testimony whereof I affix my signature.

MERRELLON r. HARDNETT. 

